The present invention relates to a method for the monitoring of the motion of a drive-operable, one or multiple part door body, particularly an overhead door, along the movement path between the open and closed position and for the interruption of this motion, particularly by switching off and over the drive in the event of an obstacle in the path of movement which the door body runs against with the following steps:
an actual course which really occurs and dependence on the movement path or the time of a physical operating value of the movement of the door body is recorded, and PA1 an interruption signal for the interruption of the motion of the door body being monitored is generated if the currently recorded value of the actual course differs by a previously determined amount from the corresponding value of a nominal course with the nominal course on the basis of a physical operating value being recorded and stored at least once before the putting into operation of the door for an obstacle-free normal operation along the movement path or the time, and to a means to perform the method in accordance with a door drive, a measuring element to measure the movement path, a measuring element to measure a physical operating value of the door motion, a memory to store the nominal course and/or actual course determined by the measuring elements in dependence on the movement path or the time and a control unit to evaluate the nominal course and the actual course and to generate an interruption signal. PA1 an interruption signal for the interruption of the motion of the monitored door body is generated if the currently determined value of the actual change of course differs to a previously determined extent from the corresponding value of a nominal change of course with the nominal change of course being determined and stored at least once before the putting into operation of the door based on the nominal course. The solution in accordance with the invention consists of the fact that in addition to the known methods a derivation of the actual course of a physical operating value of the door movement is formed at each scanned point in accordance with the movement path and that an interruption signal is generated even if a criterion is not met in accordance with the derivation determined. The nominal course of the corresponding physical operating value is here recorded and stored at least once before the putting into operation of the door for an obstacle-free normal operation along the movement path.
Such a method and such a means are known from EP-B1-0 083 947. The monitoring unit disclosed therein is based on the basic idea that the actual course of the required force to drive the door body over the movement path is compared continuously with the nominal course. If the difference between actual course and nominal course exceeds a previously fixed amount, an interruption signal is generated which switches off the door body drive or reverses its direction of movement. The nominal course is here recorded and stored at least once prior to the putting into operation of the door for an obstacle-free normal operation along the movement path.
Such a monitoring system possesses an improved hazard protection over other known monitoring systems such as electrical contacts positioned underneath yielding bulges. Nevertheless cases can still occur with such a monitoring means where the criterion to generate the interruption signal is not sufficiently sensitive. If the door body edge contacts soft obstacles, for example, the motion force for the movement of the door body increases more slowly than against a hard obstacle so that a longer period passes before the interruption signal is triggered. If, therefore, the edge of the door body laterally contacts, for example, the groin of person accidentally crossing the motion path during the movement of the door body, then is it possible that the interruption signal of the monitoring device will not be triggered early enough.